Rebreather valve



Nov. 1, 1949. R. R. MILLER ETAL REBREATHER VALVE 3 Sheets-Sheet 1 FiledApril 50, 1946 mmvroxs ROMAN R. MILLER WILLIAM H. SCHECHTER ATTORNEYNov. 1, 1949. R. R. MILLER ETAL REBREATHER VALVE 5 Sheets-Sheet 2 FiIedApril 30, 1946 Nov. 1, 1949. R. R. MILLER EI'AL REBREATHER VALVE 3Sheets-Sheet 3 Filed April 50, 1946 game/M3010. RQMAN R. MILLER WILLIAMH. S CHECHTER Patented Nov. 1, 1949 nannna'rnan VALVE Roman R. Miller,Silver Spring, Md., and William B. Schecliter, Jetmore, Kane.

Application April 30, 1946, Serial No. 665,982

towns. (01.217 1) (Granted under the m of March a, 1883, as

This invention relates to valves, and more particularly to a rebreathervalve for use with oxygen breathing apparatus. 7

Where it is necessary to enter any atmosphere that is irrespirable dueto the presence of harmful gases, vapors, dust, and smokes, or to adeficiency of oxygen, special breathing apparatus is available whichwill permitremaining in such an atmosphere for an extended period. .Inone conventional type of apparatus a compressed oxygen cylinder isemployed as a source of oxygen for breathing requirements and acompartment filled with chemicals for absorbing the carbon dioxidecontained in the exhaled breath is provided. Arecently developed type ofbreathing apparatus employs a canister-filled with a special chemicalwhich absorbs carbon dioxide and simultaneously evolves suflicientoxygen to provide for the wearers respiratory requirements, thuspermitting the elimination of the oxygen cylinder. The chemicalsused'have a limited period of useful life and consequently when theiruse is exhausted, the canister must be replaced or the wearer must leavethe atmosphere which necessitates the use of the oxygen breathingapparatus. Often this latter alternative is not feasible. It thenbecomes necessary to provide a breathing apparatus with which thecanister may be exchanged during use in a noxious atmosphere. facilityof exchange, the apparatus must be so designed that the exchange ofcanisters may be effected without any possibility of the noxiousatmosphere reaching the wearer.

An object of the present invention is to provide a new and improvedrebreather valve for use with oxygen breathing apparatus, and moreparticularly a rebreather valve which will enable ready exchange ofcanisters while preventing entrance of the atmosphere into the breathingapparatus.

- In accordance with one embodiment of this invention a rebreather valvemay be provided which when a canister is removed therefrom automaticallycloses the passage from the mask tothe canister and from the canister tothe breathihg bag, while at the same time opening a direct passage fromthe mask through the valve to the breathing bag. When a new canister isinserted in position, this causes the valve to shift position and toseal the direct passage from the mask through the valve to the breathingbag and at the same time to open the passage from the mask through thevalve to the canister and from the canister to the breathing bag. Ineither In addition to affordin amended April 30, 1928; 370 O. G. 757) 2valve position a closed system is maintained outside atmosphere isprevented from reaching the wearer of the apparatus.

'. Other objects and advantages ofthepresfli.

invention will be apparent from the following detailed description takenin conjunction with Fig. 2 is an enlarged, vertical, sectional view 7 ofthe rebreather valve shown in Fig. 1, the valve having a canister shown'fragmentarily associated therewith;

Fig. 3 is a sectional view similar to Fig. 2 show- I ing, however, theposition of the several parts of the valve when the canister is removedtherefrom;

Fig. 4 is an elevational view of the lower end of the valve as shown inFig. 3; and

Fig. 5 is a. transverse, sectional view taken substantially along theline 55 of Fig. 3.

Referring now to the drawings, and particularly to Fig. 1, it will beseen that a complete oxygen rebreathing apparatus is shown comprising asubstantially conventional mask, or face piece 5 adapted to be fittedover the wearers face and so designed that it will fit closely andprevent entrance or escape of air. 'The mask 5 is connected at its baseto a T fitting 6 in either end of which are oppositely acting fluttervalves mounted in housings l and 8. The flutter valve 1 is selected toopen in response to pressure on the right side thereof, as viewed inFig. 1, this occurring when the wearer exhales, while the valve 8 isdesigned to close in response to pressure on the left side thereof,again when the wearer exhales. When the wearer exhales, the exhaled airis thus directed through the valve 1, a flexible tube 9, connected tothe valve, and into the upper portion of a rebreather valve l0 shown indetail in Figs. 2, 3, 4 and 5. When a canister H is in position on therebreather valve 10, as will be more readily understood from thedetailed description of the rebreather valve hereinafter set forth, theexhaled air is caused to pass through the valve into the canister. Thecanister is filled with a chemical which purifies the air by absorbingthe carbon dioxide and which simultaneously evolves suflicient oxygen toreplenish the air and to render it suitable for the wearers respiratoryrequirements. By reason of the design of the canister, which forms nopart of the present invention, exhaled air is caused to travel and ' i2,extending from the left hand side thereof,

which is in turn connected to a breathing bag ii. The breathing bag ismade quite" large and is so designed that air entering at one sidethereof must traverse substantially the breadth thereof before reachingan outlet it which connects through a flexible'tube II to the end of theT-shaped fitting having the flutter valve 8 associated therewith, thebag permitting the air to cool prior to reaching the wearer of thebreathing assembly and providing a supply of air. when the-wearerinhales, the valve 1 closes and the valve 8 opens, permitting the wearerto inhale purified and replenished air from the breathing bag.

After a period of use the lengthof which is dependent on the amount ofchemical in the canister and its characteristics as well as the extentof the wearer's exertions, the chemicals in the canister becomeexhausted and the wearer must either leave the area necessitating theuse of the mask or must exchange the canister for a fresh one.Exchanging the canister ordinarily requires leaving the noxiousatmosphere because of the danger of the atmosphere reaching the wearerduring the 'priod required for exchange. In some cases, as will bereadilyapparent, this may be quite impracticable or very undesirable.Accordingly, in order to permit exchange of the canister while in anoxious atmosphere and without danger to the wearer, the rebreathervalve ill of the present invention has been provided.

Referring now to Figs. 2 and 3 it will be seen that the valve of thisinvention comprises a generally cylindrical housing having an upper orneck portion 20, a somewhat larger diameter midportion 2|, and anenlarged lower portion 22, the several portions of the housing beingillustrated as integrally formed; however, they may be separate elementsand assembled. The upper portion of the periphery of the neck 28 isthreaded to receive a collar 23 whereby a short coupling tube 24,adapted to fit into the lower end of the flexible tube 9, is mounted onthe upper side of the valve. The coupling tube 24 has a flange 25integrally formed about the periphery thereof am'acent its lower end andthe collar 23 bears against the upper side of this flange. An'annularsealing gasket 28 is positioned about the lower end of the tube and whenthe: tube 24 is assembled on the valve, as shown in Figs. 2 and 8, thegasket is compressed between the underside of the flange 25 and theupper edge of the housing portion 20, providing thereby a fluidtightconnection.

When a canister II is in position on the valve, as shown in Figs. 1 and2, a passage is opened directly through .the center of the valve fromthe upper portion 28' to the lower portion 22, the passage including asleeve 21, the upper portion of which is slidably disposed in the neckportion of the valve housing and the lower portion of which extendsdownwardly substantially to the lower end of the mid-portion 2| of thevalve housing. A second sleeve 28, connected to the sleeve 21 andaxially aligned therewith, is positioned in the lower portion 22 of thevalve housing. The upper portion 29 of the sleeve 28 is madesubstantially larger in diameter than the lower portion, which is ofsubstantially the same diameter as the sleeve 21, and the upper portionis threaded internally to engage the threaded periphery of a flange 80integrally formed at the lower end of the sleeve 21 and extendingoutwardly therefrom. The lower portion of the sleeve 28 extends beyondthe base of the housing section 22 and has fixed thereto a conical wedge34, the sides of which are apertured.- When the canister I i isassembled on the valve ill, the conical wedge serves to perforate thecap of the canister, the canister being forced upwardly 'by a large handbolt 85 fixed to the breathing -apparatus as shown in Fig. 1. In theposition shown in Fig. 2, the lower end of the sleeve 28 extends intothe center of the canister neck and is sealed to a suitable duct formedtherein. The upper edge -'of the canister neck is usually provided witha soft covering of gasket material which when compressed serves as aneffective seal. When the canister H is assembled on the valve housing asshown in Figs. 1, and 2, the periphery of the neck of the canister bearsagainst and urges upwardly a heavy ring 38 slidably disposedin the lowerportion 22 of the valve housing. The lower portion of the ring may bebeveled outwardly to provide a suitable seal, while the upper portion ofthe ring 38 is provided with an annular recess 48 in which is disposedthe lower portion of a spring 43'. The ring 86 is. urged downwardlyagainst retaining lugs '81 mounted about the peripheryof the housing 22and extending inwardly therefrom by the helical spring 43, the lower endof which bears against the base of the recess 48, while the upper end ofthe spring bears against an outwardly extending flange 44 integrallyformed with a short tube 45, which is rigid- 1y secured to a shoulder41, formed at the junction of the mid portion 2i and the lower portion22 of the valve housing, by a number of screws 48. Integrally formedwith the lower end 'of the tube 45 is an inwardly extending flange 48,the

inner edge of which bears against the periphery of the sleeve 28 andserves as a guide therefor,

maintaining axial alignment of the sleeve 28 with respect to the valvehousing as the sleeve 28 moves upwardly or downwardly as will behereinafter explained.

Considering the valve insofar as it has been described up to this point,it will be apparent that the several elements thereof combine to providea passageway for exhaled air which extends from the upper portion 20through the interior of the sleeves 21 and 28, downwardly and into thecenter of the canister i l through the apertured, conicalwedge 34. Airentering the canister through the center thereof is caused to passdownwardly, then outwardly, then upwardly, and flnallyleaves thecanister through the annular passageway formed between the lower end ofthe sleeve 28 and the neck of the canister. This air then enters thelower portion 22 of the valve, passing through a chamber formed betweenthe outer side of the sleeve 28 and the inner side of the valve position22, and upwardly through suitable apertures 48 formed in the flange 48adjacent the sleeve 28 and into an "annular chamber designatedat 58,which is bounded by the outer sides of the sleeves 21 and '28 and theinner side of the valve section 2!. A port 5| is formed in the left sideof the housing section 2! and connects the chamber 58 to the short tubel2 extending from the left side of the valve housing and connecting tothe breathing bag l5.

, Thus air entering the chamber 50 may be drawn was:

of airffrom the breathing apparatus or entrance of air into thebreathing. apparatus, a valve mechanism has been provided whereby uponremoval of a canister from the lower end of the valve housing, thepassage from'the mask to the canister described in the precedingparagraph is closed and a direct passage is opened from the interior ofthe sleeve 21 to the chamber 50 and near the lower end of along valvestem 53, which is axially disposed. with respect to the valve housingand extends from the upper portion i when the flange uis caused to bearagainst the flange 48,, the apertures 48 formed in the flange 48 "willbe effectively; sealed, as may be readily seen in Fig. 8. :Since theupper end of the valve stem-80 is slidably Journaled in the spider diskI. 51, it will be apparent that'after the flange 30 thereof to the lowerportion. The disk 52 is disposed between the flange 30 formed at thebase of the sleeve 21. and a flange 54 which is integrally formed withthe sleeve 28 and joins the enlarged upper portion 29 thereof to thelower portion 28. A layer 55 of-a soft gasket material, such as rubber,is provided on the upper surface of the disk 52 so thatwhen the disk 52-bears against the lower end of the sleeve 21, the sleeve is effectivelysealed at its lower end.

Axial alignment of the stem 53 with respect to the housing of the valveis maintained by a small radially apertured disk or spider 55 fixed tothe lower endof the stem and slidably jourment of the valve stem islimited by the length of the stub 60.

The valve stem 53 is normally urged upwardly by'a helical spring 52disposed in the lower sleeve a 28 and the lower end of which bearsagainst the inner side of the conical wedge 34 while the upper end ofthe spring bears against the under side of the spider disk 58, attachedto the lower end of the valve stem 50. In order to cause the flange 30to bear against the gasket provided on the upper surface of the valve,52 and thereby to seal the passage through the sleeve, a helical spring64 is provided and the upper end of this spring is mdunted against theunder side of the housing section 20 while the lower end of the springbears against the upper surface of the flange 30, thus urging thesleeves 21 and 28 downwardly relatively to the housing of the valve.Since the uppermost position of the valve 52 with respect to the valvehousing is fixed, downward movement of the sleeves 21 and 28 causes theflange 30 to engage the upper surface of the valve 52.

, Initial downward movement of the sleeves causes the flange 30 toengage the disk 52, as

described, thus sealing the passage through the sleeves and preventingexhaledair from leaving the valve from the lower end. .Inorder to sealthe passage through the apertures 49 formed in the flange 48 to preventatmosphere from enter ing the valve, the valve I0 is so designed that Iremoval of a canister therefrom permits the sleeves 21 and 28 to movedownwardly a sufllcient distance to cause the under side of the flange54 to bear against the upper side of the flange 48. Adjacent the outeredge of the flange 54 and on parts of this invention have been referredto as plenished.

has engaged the disk 52, the disk 52 willmove downwardly with thesleeve. When the sleeve 21 is in its lowermost position, apertures 81formed inits sides adjacent the upper end are exposed to'the chamber 50,these apertures having been previously closed by reason of this portionof the sleeve being disposed in the upper portion 20 of the valvehousing. Exposing these apertures to the chamber 50 opens a passage fromthe sleeve 21 into the chamber 50 and to the tube i2. It will beapparent from .the foregoing,

however, that this passage is not opened until the passage through thesleeves to the conical wedge 34 and through the lower portion of thevalve housing have been closed, thus preventing escape or entrance ofair into the breathing apparatus during exchange of a canister.

When a new canister is placed in position, the wedge 34 first perforatesthe cap, then reaches a point beyond which it cannot enter. Furtherupward movement of the canister, produced by tightening the hand bolt35, .then causes the rim of the canister neck 'to bear against the ring38 which is resiliently mounted to provide an effective seal, and alsocauses the sleeves 21 and 28 to move upwardly, .openingthe outer passagethrough the apertures 49 to the annular chamber 50. The valve stem 53follows until theupper end thereof strikes the fixed spider disc 51.

Thereafter, continued upward movement of the sleeves 21 and 28 causesthe valve 52 to be separated from the lower end of the sleeve 21,

thereby opening the central passage through the.

rebreather valve. The apertures 61 are closed as soon as the sleeve 21moves into the valve portion 20, preventing exhaled air from enteringthe breathing bag prior to being purified and re- It will be apparentthat a closed system is thus maintained at all times permitting exchangeof canisters in any typeof atmosphere.

Where in the foregoing description the several The invention shown anddescribed herein may be manufactured or used by or for the Government ofthe United States of America for governmental purposes without thepayment of royalties thereon or therefor.

What is claimed is:

1. A valve of the class described including a 'casing having a neckportion forming an inlet' aperture, a mid-portion of larger crosssectional size than said neck portion, and a lower portion,

said mid-portion having an outlet aperture formed in the side thereof,an annular disk disposed between said lower portion and said midportionhaving at least one aperture formed the inner side thereof is provided arim 88- of a suitable gasket material, such as rubber, so that 7therethrough adjacent the central aperture, a longitudinally movableconduit having an upper end lournalled in said neck portion and itslower end journalled through the central .aperture of said annular disk,said conduit having at least one aperture formed in the side thereof andso located that when said conduit is moved into' said neck portion saidaperture is closed but when said conduit is moved out of said neckportion a suflicient distance, said aperture opens into said midportion,a flange fixed to the periphery of said conduit and ensageable with saidannular disk to close the off-center passage therethrough when saidconduit is moved away from said neck portion, and a valve disposed insaid conduit for closcross-sectional size, and a lower portion, saidmidportion having an outlet aperture formed in a side thereof, anannular member disposed be-v tween said lower portion and said lowerportion having a central aperture formed therethrough and at least oneother aperture radially offcentered with respect to said centralaperture, a conduit longitudinally movable with respect to said housingand having its upper end joumalled in the upper portion thereof and itslower end journalled through the central aperture of said annularmember, a flange fixed to the periphery of said conduit and engageablewith said annular member to close the radially off-centered passagetherethrough when said conduit is in its lower position, resilient meansfor urging said flange into engagement with said annular member, saidconduit having at least one aperture formed in a side thereof so locatedwith respect to said conduit that when said flange is in engagement withsaid annular member, said aperture opens into the mid-portion of thevalve housing,

a valve disposed in said conduit for closing the passage therethrough inresponse to downward movement of said conduit, and resilient means forurging said valve into closed position.

' 3. In a valve of the class described, a housing, I

as'eaaav a a a a housing substantially to the mid-portion thereof, saidhousing having an outlet port formed in the side thereof andcommunicatin'g with said annular chamber, means for closing said annularchamber adjacent the lower end thereof, .and

means for closing said axial passage adjacent the lower end thereof,said axial passage having an aperture in the side thereof normallyclosed but which opens into said annular chamber when the i lower endofsaid axial passage is closed.

J aperture, a mid-portion, of larger cross sectional ing the passagethrough said conduit operable in size than said neck portion, having anaperture formed in the side thereof, and a lower portion, an annulardisk disposed between said lower portion and said mid-portion insaidcasing, a conduit, longitudinally movable to an upper and lowerposition, having its upper end journalled in said neck portion and itslower end projecting beyond the lower portion of said casing, aperforate, conical member, integral with said projecting end, adapted topuncture said canister when it is moved into sealed position withrespect to said casing and to simultaneously move said conduit to saidupper position, the said conduit having its lower end journalled throughthe aperture of said annular disk, said annular disk having at 3 and avalve mounted in said conduit for closing the passage therethrough, boththe said aperture and said passage being closed when said conduit is inits lower position.

ROMAN R. MILLER.

WILLIAM H. SCHECHTER.

REFERENCES crrEn The following references are of record in the 5 file ofthis patent:

UNITED STATES PA'I'ENTS Number Name Date 2,187,371 Cannon Jan. 16, 19401 2,343,901 Groves Mar. 14, 1944 2,349,137 Brown May 16, 1944

